共查询到3条相似文献，搜索用时 5 毫秒
1.
- 1. In 1995, the IUCN implemented new definitions to be used when drawing up red lists. However, in addition to being imprecise for fish species, these remain difficult to apply.
- 2. This paper describes a more exhaustive method under the IUCN (1995) definitions based on six quantitative and qualitative criteria where scientific data are given the greatest possible weight, as compared with ‘expert opinion’. This dual system makes it possible both to allocate an IUCN category to each species, and to rank each species within a particular category according to given scores, so that priorities can be determined.
- 3. The new Red List for French Freshwater Fish drawn up with this method contains 27 species, or 54% of the French native fauna. Three species are extinct (EX), four are critically endangered (CR), two are endangered (EN), 14 are vulnerable (VU), and four are at lower risk (LR).
- 4. Based on sounder scientific grounds, this list modifies and replaces the one drawn up in 1992. In effect, it makes it easier to argue for the presence of one species in one category rather than in another.
2.
3.
《水产资源保护:海洋与淡水生态系统》2018,28(1):55-67
- DNA‐based studies have uncovered cryptic species and lineages within almost all freshwater fishes studied thus far from the Cape Fold Ecoregion (CFE) of South Africa. These studies have changed the way the CFE is viewed, as almost all stream fishes that were previously considered to be of low conservation priority, because they were perceived to have broad geographical ranges, contain multiple historically isolated lineages, many of which are narrow‐range endemics.
- As stream fishes of the CFE are of conservation concern owing to threats mainly posed by habitat degradation, invasion by alien species and hydrological modification, re‐evaluation of the distribution and conservation status of newly identified unique lineages is required to inform the development and implementation of effective conservation and management strategies.
- The present study conducted an IUCN Red List conservation assessment of a newly identified lineage of the Galaxias zebratus species complex (hereafter referred to as Galaxias sp. ‘Joubertina’) to identify key threats and provide recommendations to conservation authorities on appropriate measures to reduce extinction risk.
- The lineage met the qualifying threshold for the Endangered category because of its very restricted geographic range, few remaining secure populations, small known population sizes and the intensity of threats to most of the populations. Only six populations remain, one of which could be an ‘extralimital’ population potentially established through an inter‐basin water transfer scheme.
- Galaxias sp. ‘Joubertina’ is threatened by invasive piscivores, habitat degradation and excessive water abstraction. These impacts have fragmented remnant populations, raising concerns about potential long‐term adverse impacts on genetic diversity and evolutionary potential of this lineage.
- Immediate conservation measures should protect remnant populations from further impacts, while long‐term measures should aim to restore historical connectivity to reduce the potential deleterious effects of inbreeding in the small isolated populations.